The present invention relates generally to digital graphic display processors, and more particularly, to a multifunction graphics rendering processor which provides both multiple hardware based graphics generating capability and programmable general purpose processing.
Real time digital electronic displays are used in many applications such as military command and control workstations and air-traffic control systems. In these displays, the displayed information typically comprises real-time processed data generated by a host processor adapted to receive real-time information from one or more radars, communications systems and/or other data processors. These data are combined with one or more graphic primitives, such as polylines, vectors, circles, ellipses or polygons, along with generated alphanumerics, mask areas and texture patterns to provide a relatively easily understood comprehensive graphic display on an output device such as cathode-ray tube. In contemporary systems, the various components of the graphics display such as the graphic primitives, mask windows, fill texturing and the like are provided either by a general purpose computer based graphics generator or by a hardware specific graphics generator. Of these, general purpose graphics generators offer system versatility but usually must sacrifice some degree of system performance for ease of programming. On the other hand, hardware specific graphics generators, called cogenerators, provide good system performance and sacrifice programmability.
Increasing demands on military command and control systems, military and civil air-traffic control systems and the like have created a need for a high performance multifunction graphics cogenerator which, in addition, provides a versatile and easily implemented programming capability. It is therefore an objective of the invention to provide a multifunction cogenerator that is a high performance two dimensional graphics engine providing a modular solution to a wide variety of graphic system applications. The multifunction cogenerator is implemented as a integrated circuit chip using large scale integrated circuit logic. The multifunction cogenerator combines both general purpose processing capability with hardware implemented graphics algorithms creating an innovative graphics engine. The multifunction cogenerator performs a complete set of graphic primitives or operations as well as performs general purpose processing functions. This combination allows a user to perform complex graphics operations with minimal required programming. A unique feature of the multifunction cogenerator is provision of two separate drawing channels in parallel within the same device. Each channel provides a command input register and can service a separate host processor if desired. The multifunction cogenerator services one channel at a higher priority than the other solving many problems associated with high performance graphics displays.